BACKGROUND:Black Holes are dangerous obstacles found in Super Mario Galaxy. If Mario (or Luigi) falls off of some ledges or misses his target with something like a Sling Pod, he could be sent spiraling into one, making him lose a life.
After Bowser was defeated, his sun turned into a black hole and nearly sucked up Mario, Princess Peach, Bowser's fleet, Princess Peach's Castle, and the Comet Observatory. The fleet was destroyed, but the Lumas stopped it before it did any more damage.